Jaw crusher



E. B. SYMONS Jan. 15, 1935.

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JAW CRUSHER l iled April 9, 1930 4 Sheets-Sheet 3 r w m w J PatentedJan. 15, 1935 .mw OBUSHEB Edgar B. Simona, Hollywood, Calif., assignorto Nordberg Manufacturing Company, Milwaukee, Wia, a corporation ofWisconsin Application April 9, 1930, Serial No. 442,755 15 Claims. (01.83-53) My invention relates to an improvement in crushers, andparticularly to an improvement in jaw crushers. A particular embodimentof myinvention is a jaw crusher having one normally fixed jaw. and anormally moving jaw together with means for moving the moving jaw towardand away from the normally fixed jaw. One object of my invention is toobtain a product more uniform than that prevailingly delivered by jawcrushers now on the market. Another object is to increase the reductionobtained from such a jaw crusher. Another object is to reduce theproduction of fines in Jaw crushers. Another object is the provision ofmeans for relieving the opposed crushing members when tramp iron oruncrushable material passes therebetween. Another object is theprovision of means for adjusting or setting the relative angle of thetwo jaws. Other objects will appear from time to time in the course ofthe specification and claims.

Certain matter pertaining to the lubrication features described andshown herein, but not claimed, are claimed in applicant's copendingapplication Serial Number 470,277, filed July 24, 1930, now Patent No.-1,874,830.

I illustrate my invention more or less diagrammatically in theaccompanying drawings, where- Figure 1 is an end elevation;

Figure 2 is a section on the line 2-2 of Figure 1;

Figure 3 is a side elevation;

Figure 4 is a section on the line 44 of Figure 2; and

Figure 5 is a section on the line 5-5 of Figure Like parts are indicatedby like symbols throughout the specification and drawings.

Referring to the drawings- A generally indicates any suitable base orfoundation or surface upon which the crushing machine may be mounted.The crushing machine frame generally indicated as A includes anysuitable bottom plate or flange portions A which may be bolted, as bythe bolts A to the foundations A. Preferably formed integrally with theplates or flanges A are the upwardly extending frame members A betweenwhich is formed the tank portion having the bottom wall A, the sidewalls A A", the top wall A and the transverse baflle or partition Adepending from the top A.

In the upper portion of each of the members A is a bearing or shaftengaging portion B to which may be locked the opposed shaft engagingbushings.

portion B as by the bolts 18 and nuts B The shaft 8* is thereby mountedon and locked in relation to the frame members A, extending transverselyand horizontally between them. Surrounding said shaft B is a bearingbushing 13 of any suitable anti-frictional or wear taking material.

surrounding the shaft 3*, and adapted to rotate thereabout, is the hub Cfrom which extends the jaw structure proper C Preferably the bushing B'is secured to and rotates with the hub 0, about the outer surface of theshaft 3*. As strengthening and reinforcement for the plate C areprovided a plurality of ribs C which extend, as shown in Figures 1 and2, from the hub C downwardly along and beneath the plate C Transverselyconnecting the ribs C is a .transverse rib C having in it a plurality ofenlargements in the form of perforated bosses C The ribs C terminate attheir lower or outer ends in a transverse rib C somewhat lower than therib C. A corresponding rib C extends across the bottom of the plate Cthe ribs C and C" being connected by longitudinal ribs C to form ineffect a box structure, the purpose of which will later appear. The ribsC are provided with apertures C in enlargements or lugs C projectingfrom the ribs.

In order to actuate the jaw a driven shaft D is provided with aneccentric portion D The shaft may be actuated as by the pulley orpulleys D, but it will be understood that any suitable drive may beemployed. The shaft D may rotate for example in bearings D D formed inor associated with the opposite frame members A. D indicates anysuitable bearing Surrounding the eccentric portion D of the shaft is asplit sleeve formed with the boss D and D which may be locked togetheras by the bolts D' and nuts D Within the sleeve so formed, andsurrounding the eccentric portion D is any suitable bearing bushing orbushings D indicated in Figure 2 as split. Upwardly projecting from themember D is an arm D having inset in its outer surface a hearing blockD". A- corresponding bearing I block D" is inset in the bottom of thejaw plate C and a roller rod or bearing rod D is interposed between,them, the blocks being with the roller D" with the opposed blocks D D",thus maintaining a firm and constant driving connection I provide thefollowing.

Extending through the apertures C of the lugs C" is a tube E the ends ofwhich pass through eye-bolts E The eye E of each such bolt is held uponthe end of the tube E, as by a washer P which may be fashioned in anysuitable manner upon the tube E. I may for example employ a cotter pinI. It will be understood that the ends of the tube E pass outwardlythrough the casting and that the eyebolts E are exterior to the membersA of the casting. This aperture is indicated for example at I in Figure3, the aperture being of suilicient size to permit a substantialmovement of the tube E in relation to the frame. The aperture alsopermits inspection of interior parts. Each eye bolt E passes through alug I formed on the exterior of the frame membed A and apertured as at Ito permit the bolt to pass therethrough. An abutment 1', below said lug,is mounted upon each eye-bolt E in the form of a stout washer which maybe positioned as by the nuts 1' upon the screwthreaded end portion 1 ofthe eye-bolt. Compressed between the abutment or washer I and the lug 1is indicated a spring I". It will be understood that the spring tends todraw the plate C downwardly toward the shaft D, and thereby maintains aconstant working and bearing connection between the roller D and theopposed blocks D and D".

As a bearing or wear taking member to effect the actual crushing I mayemploy for example the face or crushing plate G. Its opposed edges arebevelled as at G G". The lower bevelled edge ('5 is gripped by theoverhanging portion (3 of the lower edge of the plate C The upper edgeis clamped, as by the wedge block G. As shown in Figure 2 the plate C isprovided with a bevel, outwardly inclined surface G and, as will be seenfrom Figure 2, the wedge block G performs the double function of drawingdown the upper edge of the plate G, and of thrusting the plate Glongitudinally against the overhang G at the bottom of the plate C. Thewedge blocks G may be drawn down as by the bolts G with their nuts G",the bolts passing through the bosses C G indicates a wear taking plateadapted to protect the hub C from battering. It is removably mounted, asby the bolts G with the nuts G. G is a batter plate bolted as at G tothe lower edge of the plate C below the lower edge of the wear plate G.

The jaw plate C is also provided with side flanges G upwardlyprojecting, and generally aligned with the downwardly projecting flangesC. The flanges C support and align the side plates G. The plates G havethe additional function of guiding the material passing between thecrushing jaws, and preventing lateral escape from the crushing space.These plates G which are removable and renewable, move unitarily withthe lower jaw structure.

It will be understood that, opposed to the movable lower jaw belowdescribed, is an upper jaw which is normally fixed. I provide means,however, for permitting movement of the upper jaw in case uncrushablematerial, such as tramp iron, passes through the crushing cavity.Referring for example to Figures 3 and 5, it will be seen that the sideframe members A are provided at their upper edges with laterallyexpanded portions K in the fgrg of flanges laterally outwardly extendingfrom the main web or plate A. These flanges are provided with an outerdownwardly turned portion K The ends are supported for example by theinclined edged webs K formed preferably integrally with the plate A. Anintermediate web or support K may also be employed. At two points,preferably adjacent the opposite edges of the portion K, it is recessedas at K to receive cylindrical projections K from the jaw platesupporting element generally indicated as L. These members K are in theform of cylinders with tapered expansions K at the outer ends, andcorresponding tapered portions K at the inner ends. The apertures K areformed, as shown in Figure 5, to conform to the cylindrical conicportions K K and K'. The members K are normally held seated in theposition in which they are shown by the securing caps or abutment platesK which overlie them and which are apertured or formed as at K toconform to them. These members K are downwardly thrust againstthemembers K and the abutment webs or fianges K, for example by theemployment of a plurality of bolts K These bolts extend through themembers K and the flange K, out of line with the members K Abutmentmembers K" are provided and between the members K and the lower surfaceof the flange K are compressed a plurality of springs K. K indicate locknuts for the tops of the bolts K and K indicate nuts or washers for thebottoms. It will thus be seen that the springs K normally draw themembers K downwardly toward the flanges K, whereby the jaw structurebelow described is normally held fixed in relation to the frame membersA. The jaw plate supporting structure generally indicated as L isassociated with and preferably integral with the members K and overliesthe moving jaw plate G. Each transversely aligned pair of members K isjoined by an upper bridge structure or member L and a lower bridge L,said bridges being connected by bosses L and by ribs or webs L Thebosses L are apertured as at L for the passage therethrough of securingbolts L headed at their lower ends as at L and screwthreaded at theirupper ends as at L to receive any suitable locking nuts L L is anabutment plate, through which the bolts pass, positioned above the upperbridge member L Beneath it are a plurality of slightly yielding washersor layers of any suitable substance, for example fabric, indicated as L.This more or less yieldable material prevents snapping of thebolts dueto the inertia of the upper jaw plate when the springs are compressedowing to the passage of tramp iron through the machine.

M generally indicates a carrier for the lower jaw plate proper M whichmay be secured thereto for example by the overhanging portion M and thewedge block M with its securing bolt M The member M is provided at eachend with the transverse integral portion generally indicated as M eachsuch portion having in the sides thereof a plurality of recesses M withpenetrating slots M", whereby the entire structure can be hooked uponthe ends of the bolts L with the heads of such bolts L penetratingwithin the recesses M". Between the upper face of each bridge member Mand the lower face of each bridge member U I may employ one or morewashers or shims M.

In order to maintain proper lubrication of the moving parts and toprevent the access of dust to moving parts I provide the followingsystem. Projecting upwardly about the connection D between the eccentricD and the lower jaw structure C I provide a surrounding housingstructure generally indicated as O. This housing is bolted as at O tothe oil container which includes the walls A A, A", A and projectsupwardly about the member D" It terminates in two concentric andsomewhat arcuate walls 0 O opposed to washers or wiping members 0 O onthe flanges C and C" respectively of the plate support or jaw C It willbe understood that the form of the opposed parts is such that as the jawoscillates about its center of rotation the wiping members contact theexterior of the walls or members 0 O preventing any accessof dust to theclosed housing thus formed. 0 indicates a battle adapted further todirect what slight dust does penetrate the housing away from the bearingroller D. It will be understod. that the packing or wiping means 0 O arecontinued as at 0" along the flanges or walls C which connect theflanges C C. This structure will be clear from Figure 4.

I may provide any suitable oil circulating means for delivering oil fromthe oil housing to the bearings. I indicate for example a gear P uponthe shaft D which gear meshes with and drives a pinion P The shaft P,associated with the pinion, may drive any suitable pump mounted forexample in the pump housing P and not herein shown in detail. Pindicates an oil delivery pipe extending from the pump housing, alongwhich the pump is adapted to direct a flow of oil. P indicates an oilpipe extending from the oil reservoir to the pump, through which oil isdrawn for delivery along the pipe P". P communicates with an oil duct Pwhich extends to the packing gland P and communi cates with an axialpassage P in the shaft D. An outlet P for the said duct 1-" is adaptedto deliver oil to the bearing surface of the eccentric D The oil mayescape along the bushing D and is delivered thereby to the bearings Dwhich are thus lubricated by the same oil streams or oil delivery. Pindicates an oil delivery pipe extending to the packing gland P andtherethrough to the axial or longitudinal passage P in the shaft B. Pindicate oil outlet ducts through the bearing surface of said shaft.They extend for example to the groove P in the bushing B P indicatereturn oil ducts whereby the oil drains back to a point adjacent theroller D which is thereby lubricated. The oil drips back into thereservoir. The baflie 0 serves to prevent the drip or delivery of oil tothe wiping member 0 P indicate oil return ducts from the oil collectinghousings or members P", in one of which the pump drive is positioned asshown in Figure 1. Thereby all the oil delivered to the bearings D isreturned to the oil reservoir. P indicates an oil inlet pipe, having thecap P whereby any desired quantity of oil may be delivered to the oilreservoir.

It will be observed that the oscillation or movement of the lower jawstructure progressively increases and diminishes the volume of airwithin the oil reservoir, owing to the fact that the cavity of the oilreservoir opens to the lower face of the plate C there is a tendency tosuck air into the oil housing and as the jaw falls there is a tendencyto expel air. In order to prevent admission of dust by such air flow Iprovide an air inlet shown As the jaw rises for example in Figure 2 asfollows. Q indicates the main air inlet passage closed by a perforatedplate Q The perforations Q are masked by a flexible diaphragm Q whichpermits move ment of air downwardly through the apertures, but resistsmovement of air upwardly through the apertures, being flattened againstthe plate Q by any upwardly exerted air pressure. Q indicates a passagein communication with the top of the plate Q. It is surrounded by agenerally rectangular housing Q with a perforated bottom Q and anysuitable dust retaining fill ing Q", for example of fiber. Q indicates aclosed cover which, however, may be removed, as by loosening of the wingnuts Q mounted on the pivoted eye-bolts Q The result is the admission ofdust-free air into the oil housing. through the aperture Q. associatedwith means for preventing retrograde movement of air upwardly throughthe aperture Q. It will be understood from this structure that as thejaw plate C rises, air is drawn through the aperture Q. As thejaw fallsair is forced downwardly around the packings O 0 O", blowing away thedust, or preventing the inward movement of dust or dust filled air intothe oil housing.

It will be realized that although I have described and shown a practicaland operative device, nevertheless many changes may be made in the size,shape, number and disposition of parts without departing from the spiritof my invention. I therefore wish my description and drawings to betaken as in a broad sense illustrative and diagrammatic rather than aslimiting me to my specific showing. In particular it will be understoodthat I do not wish to be limited, except so far as I limit myself in myclaims, to any particular shape or profile or angle of crushing jaw orplate, as I may vary them considerably without destroying thecharacteristic action of the crusher.

The use and operation of my invention are as follows:

I employ a jaw crusher having preferably an inclined, lower jaw, and anupper jaw overhanging or overlying a substantial proportion of the areaof the lower jaw. In the particular form of my device herein shown thelower jaw C is pivoted adjacent or above the upper edge of its effectivecrushing area, and is oscillated or rotated, through a rathersubstantial are, about its pivot, in such fashion that the travel orthrow of the crushing plate G increases progressively from top tobottom. The driving connection is made from the lower portion of thecrushing jaw, whereby the eccentric D by its rotation oscillates orpivots the jaw C giving the plate G its characteristic crushingmovement. The upper or overhanging jaw M, with the crushingplate M isnormally fixed upon the frame of the crusher. However, I provide ayielding connection between the upper jaw structure and the frame,whereby it may give in response to the passage of uncrushable materialthrough the crushing machine. This obviates or greatly reduces theprobability of stop-. page or breakage. As the abnormal stress may occurat a variety of points along the plate M I provide a double tiltingconnection, whereby either the top or the bottom of the jaw may recedefrom the opposed jaw. Assume that a large mass of uncrushable materialdrops between the opposed crushing plates and engages the plate Madjacent its upper edge, the plate will then tilt about the lower pairof members K the upper edge of the plate M tilting away from the upperpart of the plate G. On the other hand, if the smaller uncrushable massor member is wedged between the opposed crushing plates adjacent theirlower edges, the jaw M may tilt about the upper pair of members K. It ispossible but not likely that an uncrushable mass may engage the centralportion of the jaw M and cause both ends to lift at once. In any casesuch a lifting movement would be so slight that upon its relief thesprings K would draw the member K back into position and there would beno permanent displacement of the members K".

A characteristic method of operation of the present device is theemployment of a more. or less restricted feed, whereby a relativelysparse flow of the material to be crushed is delivered to the upperportion of the crushing zone defined by the opposed plates G and M Whenthe machine is set up as shown in the drawings, and the drive shaft D isrotated, the eccentric D rotates the lower jaw toward and away from theupper jaw. The material to be crushed is fed in from above, fallingfreely under gravity into the crushing space between the opposed plates.As the lower jaw rotates or oscillates, material will be wedged orpinched between it and the overhanging upper jaw. As soon as the lowerjaw begins to recede from the upper jaw, each particle will commence tofall freely away from the upper jaw, the distance of its fall dependingon the relation between the acceleration due to gravity, the rate andlength of movement of the jaw, the angle of the jaw, and the size of theparticle. Since the upper jaw overhangs the lower, the dropping actionof the material away from the crushing surface of the upper jaw isobtained by withdrawing the lower jaw with sufficient rapidity andthrough an excursion of suflicient length downwardly and slightlylaterally away from the effective crushing surface of the upper jaw.Therefore, after each crushing impact the lower jaw is moved through anexcursion of such length and at such a rate that it recedes from theupper jaw faster than the material can drop. The particles will fallgenerally vertically downwardly from the upper jaw, after the lower jawhas been withdrawn, until they again strike the lower jaw. They willthen move downwardly along the face of the lower jaw until the lower jawreturns again near enough to the upper jaw to nip the particles betweenthe two jaws. When the lower jaw reaches a point at which the distancebetween its surface and that of the upper jaw is equal to the diameterof the particles between the two jaws, then the downward movement of theparticles ceases, and they are again crushed. This alternation ofvertical drop and crushing conveying movement continues until theparticles being crushed have escaped from the crushing zone, and passdownwardly across the lower edge of the lower plate G, and over theguard or deflector G.

The action to which the articles being crushed is subjected may bedivided into three parts. First, there is a free drop by gravity, whichmay take place when the material is initially fed to the crushing zone,and which repeated after each crushing impact. Second, there is asupporting engagement between the lower jaw and the particles, afterthey have dropped so far as to engage the lower jaw, but are not yetactually nipped between both jaws. Finally, there is the actual crushingimpact, which begins on the up-stroke of the lower jaw, when thedisstance between the two jaws is no greater than the diameter of theparticles being crushed. The crushing nip continues and effects thedesired reduction, after which case the next following free drop underthe influence of gravity.

Assuming a restricted feed, the initial drop, the sliding movement downthe lower jaw, and the crushing impact against the upper jaw is effectedwith a crushing zone relatively sparsely filled with material. In orderto obtain a positive sizing for the particles crushed, I provide a zoneof parallelism X at the lower edges of the opposed jaws or plates, inwhich zone the opposed faces of the plates are parallel at their pointof closest approach. The length of the zone of parallelism is governedby two main factors: first, the speed imparted to the material bygravity, gravity being a constant force, and second, the interval oftime between the crushing impacts, during which the material ispermitted to drop as it is released by the increasing distance betweenthe opposed jaws, and during which it slides along or moves across thelower jaw prior to the crushing nip. The interval of time is governed bythe speed of operation of the machine. The length of the zone ofparallelism must be such that all the material passing therethrough willremain in the zone so long as to be caught at least once between the twojaws at their moment of closest approach.

The maximum distance between the opposed jaws is far greater than theultimate size of the material being crushed.

In any crushing process the production of fines or dust is inevitable,but I reduce such degradation to a minimum, as I crush with a sparselyfilled crushing zone, and therefore with a minimum of crushing orgrinding contact between particles. As the particles drop from theoverhanging upper jaw to the lower jaw, they tend to spread out upon thesurface of the lower jaw and to slide or roll or skip freely downwardlythereacross. Thus when the material is crushed the particles tend not tobe superposed upon each other and are not compacted but are freelyspread or scattered in the crushing zone. The larger particles projectfarther from the surface of the lower jaw than the smaller, and arecrushed first. Particles which have for any reason been crushed at thepreceding crushing impact to a size less than the governing minimumdistance between the two jaws at the next impact, are not crushed atall. The total throw of the lower jaw, stated in terms of its functionor effect, is divided into a conveying excursion, during the time whenthe material Is not nipped, and a crushing excursion, which continuesfrom the beginning of the crushing nip to the termination of thecrushing nip or effect of any particular excursion of the jaw. Theactual crushing excursion is in general substantially smaller than theconveying excursion, and furthermore decreases progressively frcm top tobottom of the crushing zone. This is so since the material issuccessively reduced to smaller and smaller size, while the actual throwof the lower jaw increases progressively from top to bottom. Forexample, in fine reduction, if the movement at the lower edge of the jawwere, say, 2 /2 inches, the actual .crushing excursion might be not overA of an inch in length.

In connection with maintaining the feed of material through thecrushingzone, and in order to prevent the wedging of small particlesabout 5 the edges of the jaws I have formed the lower jaw with upwardside extensions G which support the cheek plates G. .These cheek platesare preferably removable and replaceable, and may be of any suitablematerial, for example manganese. Assume that material is caught betweenthe upper jaw plate M and the cheek plate G when the lower jaw drops,the cheek plate moves down, moving with the lower jaw, and tends to pullthe caught material downwardly, and to free it from the edge of the jawplate M As the opening between M and G increases, this material can falllaterally into this increasing open space, and falls back into thecrushing zone. At every stroke of the lower jaw the cheek plate freesthe trapped material, and tends to feed it back into the crushing zone.This is particularly important in fine reduction, to prevent thetrickling of oversize material downwardly along the edges of the jawplates. This would be possible where the closest approach of the jawplates is less than the interval between the edges of the jaw plates andthe cheek plates.

I claim:

1. In a jaw crusher, a normally fixed jaw and a moving jaw opposedthereto, the moving jaw being oscillatable about a normally fixed pivotthrough a rectilinearly defined path and actuating means for said movingjaw including an eccentric link and a direct driving connection betweensaid eccentric link and said jaw, a housing about said eccentric linkand wiping connections between the edges of said housing and the Jaw.

2. In a jaw crusher, a frame including upstanding frame elements, amovable jaw pivoted to said frame elements adjacent its upper edge, anda normally fixed jaw tiltably mounted upon said frame elements, andyielding means for normally maintaining it in fixed position, said meansbeing adapted to permit it to tilt in response to a predetermined excesspressure within the crushing zone between the two jaws, includingclamping members associated with said frame elements, and yielding meansfor drawing said clamping members against said frame elements, whichinclude guiding members associated with said clamping members andpenetrating said frame elements, spring abutments upon said guidingmembers and springs compressed between said abutments and frameelements, the normally fixed jaw including portions interposed betweensaid frame elements and said clamping members.

3. In a jaw crusher, a normally fixed jaw and a moving jaw opposedthereto, and actuating means for said moving jaw including an eccentricmember, and a direct driving connection between the eccentric member andthe jaw, a housing about the eccentric member, wiping connectionsbetween the edges of the housing and the jaw, and air inlet and outletmeans for said housing, said jaw being adapted, in response to itspulsating movement, to draw air into and to expel air from said housing.

4. The structure of claim 3 which includes the provision of means forexpelling air from the housing past said wiping connections.

5. The structure of claim 3 which includes the provision of means forexpelling air from the housing past the wiping connections, the airinlet means being effective to admit air to the housing at a point moreor less distant from the wiping connections. a

6. The structure of claim 3 which includes the provision of means forexpelling air from the housing past the wiping connections, the wipingconnections being adapted to prevent the passage of air inwardlytherethrough into the hous- 7. The structure of claim 3 whichincludesthe provision of air cleaning means adapted to admit cleaned airinto the housing.

8. In a jaw crusher, a normally fixed jaw and a movingjaw opposedthereto, a frame element upon which said normally fixed jaw is mounted,a tilting connection intermediate said frame element and said jaw andyielding means adapted to hold said "jaw normally in fixed position andadapted to permit it to tilt in relation to said frame element inresponse to predetermined excess stresses, said tilting connectionincluding trunnions associated with the jaw, and arcuate bearing membersassociated with the frame and adapted to receive the trunnions, theyielding means being adapted to hold said trunnions normally seatedagainst said bearing members, one such tilting member being providedadjacent the top and one adjacent the bottom of the jaw.

9. In a jaw crusher, a base, a frame upstanding from said base, amovable jaw pivoted about a normally fixed pivot adjacent the upperportion of said frame, and means for reciprocatingly rotating it aboutsaid pivot through a predetermined are, an opposed jaw normally fixed inrelation to said frame, said normally fixed jaw overlying said movablejaw throughout a substantial proportion of its area, and yielding meansfor normally holding the opposed jaw fixed in relation to said frame,said means being yieldable to permit a recession of the normally fixedjaw from the movable jaw-in response to predetermined pressures, tiltingconnections being interposed between the normally fixed jaw on the frameadjacent the upper and lower por tions of the jaw, adapted to permit thejaw to tilt in relation to said frame selectively about the axes ofeither of saidtilting connections.

10. In a jaw crusher, a normally fixed jaw and a moving jaw opposedthereto, a frame element upon which said normally fixed jaw is mounted,a tilting connection intermediate said frame element and said jaw andyielding means adapted to hold said jaw normally in fixed position andadapted to permit it to tilt in relation to said frame element inresponse to predetermined excess stresses, said tilting connectionincluding trunnions associated with the jaw, arcuate bearing membersassociated with the frame and adapted to receive said trunnions, andyielding means for holding said trunnions normally seated against saidbearing members.

11. In a jaw crusher, a base therefor, a normally fixed jaw and a movingjaw opposed thereto, driving means for said moving jaw, a housing forsaid driving means in said base, said driving means being located withinsaid housing, said housing being adapted to contain a supply of oil,means for circulating said oil to the various bearings of the jawcrusher, including a pump and means for actuating it, said housing beingin part closed by the moving jaw itself, an overlapping connectionbetween housing and jaw, driving means extending between and beingsurrounded bysaid overlapping 0011-. nection, and means for admittingair into and expelling air from the housing in response to 'the movementof the jaw.

12. In a jaw crusher, a base therefor, '9. nor-- mally fixed jaw and amoving jaw opposed thereto, driving means for said moving jaw, a housingfor said driving means in said base, said driving means being locatedwithin said housing, said housing being adapted to contain a supply ofoil, means for circulating said oil to the various bearings of the jawcrusher, including a pump and means for actuating it, said housing beingin part closed by the moving jaw itself, an overlapping connectionbetween housing and jaw, driving means extending between and beingsurrounded by said overlapping connection, and means for admitting airinto and expelling air from the housing in response to the movement ofthe jaw. and means associated with said air admitting means for cleaningthe air admitted to the housing.

13. In a jaw crusher, a frame including upstanding frame elements, amovable jaw and a normally fixed jaw tiltably mounted upon said frameelements, and yielding means for normally maintaining it in fixedposition, said means being adapted to permit it to tilt in response to apredetermined excess pressure within the crushing zone between the twojaws, including clamping members associated with said frame elements,and yielding means for drawing said clamping members against said frameelements, which include guiding members associated with said clampingmembers and penetrating said frame elements, spring abutments upon saidguiding members and springs compressed between said abutments and frameelements, the normally fixed jaw including portions interposed betweensaid frame elements and said clamping members.

14. In a jaw crusher, a frame including upstanding frame elements, amovable iaw'mounted within said upstanding elements and means forimparting to it oscillation in a rectilinearly bounded path, a normallyfixed jaw movabiy mounted in relation to said frame elements and meansfor normally holding it in said fixed position, including abutments onsaid frame elements positioned at opposite sides of the path of movementof the movable jaw, yoke means extending to the rear of the jaw providedwith laterally extending projections, said projections bridging saidabutments, and means for urging said yoke means toward said abutmentmeans, including cap members engaging said projections, and a pluralityof springs positioned along each side of said frame exteriorly of thepath of movement of the movable jaw, at opposite sides thereof, springabutments on said frame, movable spring abutments positioned adjacentsaid frame elements,'said springs being compressed between saidabutments, and tension members connecting said movable abutments withsaid cap members.

l5. Ina jaw crusher, a frame including upstanding frame elements, amovable jaw mounted within said upstanding elements and means forimparting to it oscillation in a rectilinearly bounded path, a normallyfixed jaw movably mounted in relation to said frame elements and meansfor normally holding it in said fixed position, including abutments onsaid frame elements positioned at opposite sides of the path of movementof the movable jaw, yoke means extending to the rear of the jaw providedwith laterally extending projections, said projections bridging saidabutments, and means for urging said yoke means toward said abutmentmeans, including cap members engaging said projections, and a pluralityof springs positioned along each side of said frame exteriorly of thepath of movement of the movable jaw, at opposite sides thereof, springabutments on said frame, movable spring abutments positioned adjacentand exterior to said frame elements, said springs being compressedbetween said abutments, and tension members connecting said movableabutments with said cap members.

EDGAR B. SYMONS.

